arduino uno connect hotspot in mobile ph which way ?
You need a WIFI shield
the official wifi shields are insanely expensive and offer limited features. replace your arduino with an esp8266 (around 6$)or an esp32 (around 12$) nodeMCU you'll get the MCU and the wifi hardware i a small, low power, form factor that can be programmed within the arduino IDE. if you want to stay with your arduino you can buy a 2$ esp-01 board and connect to wifi via serial AT commands